Baryon Octet Electromagnetic Form Factors in a confining NJL model

TL;DR

This paper investigates the electromagnetic form factors of baryon octet particles using a confining NJL model with corrections from vector mesons and pion cloud, showing good agreement with lattice QCD results.

Contribution

It introduces a confining NJL model with proper-time regularization and additional corrections, providing a comprehensive analysis of baryon electromagnetic form factors.

Findings

Charge radii patterns differ from naive expectations.

Magnetic radii align with dressed quark mass expectations.

Results are consistent with recent lattice QCD extrapolations.

Abstract

Electromagnetic form factors of the baryon octet are studied using a Nambu--Jona-Lasinio model which utilizes the proper-time regularization scheme to simulate aspects of colour confinement. In addition, the model also incorporates corrections to the dressed quarks from vector meson correlations in the t-channel and the pion cloud. Comparison with recent chiral extrapolations of lattice QCD results shows a remarkable level of consistency. For the charge radii we find the surprising result $r_{E}^p < r_{E}^{\Sigma^+}$ and $|r_{E}^n| < |r_{E}^{\Xi^0}|$, whereas the magnetic radii have a pattern largely consistent with a naive expectation based on the dressed quark masses.